Hemispheric stroke reduces an individual's ability to successfully generate voluntary movement of the contralateral limb. Stroke-induced impairments typically include weakness, spasticity, and impaired movement coordination. While there is an increasing understanding about the origins and role of weakness and spasticity in mediating stroke impairment, less is known about the origins of the impaired coordination, which is frequently the most important and long-lasting source of disability. The primary objective of the proposed research is to determine how well a stroke survivor's internal model (IM) of action for their impaired limb corresponds to its actual physical performance. We will address this issue by considering in turn, the internal processing of proprioception muscle-based sensation of motion and mental motor planning for the impaired limb. We believe this investigation will provide a greater understanding about the nature and extent of disturbances in cognitively-based processing of sensation form and action of the impaired limb, and how directly they may be reflected in action execution. This investigation builds from methods and approaches I learned during my graduate and postdoctoral training in cognitive psychology and neuroscience while providing an opportunity to expand my methodological techniques and to focus on issues of brain and behavior with my new questions about functional recovery in mind.